753027

Appears in sequences

• a(n) = -a(n-1) - 2*a(n-2).at n=40A001607
• Expansion of 1/(1 - 3*x + 4*x^2).at n=19A049072
• a(n) is the unique odd positive solution x of 2^n = 7x^2+y^2.at n=39A077020